Dredge



3S11eets-Sheet 1 A. K. STONE. DREDGE.

(No Model.)

Patented Mar. 22, 1892.

. 3 Sheets-Sheet 2-. A. K. STONE.

DREDGE'.

(No Model.)

Patented Mar. 22, 1892.

lllnni 4m 2 M u 3 Sheets-Sheet 3. A. K.STONE.

DREDGE.

(No Model.)

No. 471,404. Patented Mar. 22, 1892.

170091156071- WWI-draw, My

wfleases.

UNIT D STATES PATENT OFFICE.

ANDREWV K. STONE, OF BOSTON, MASSACHUSETTS.

DREDGE.

SPECIFICATION forming part of Letters Patent No. 471,404, dated March 2'2, 1892. Application filed September 16,1891. Serial No. 405,788. (No model.)

To all whom it may concern:

Be it known that 1. ANDREW K. STONE, of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Dredges, of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention has for its object the production of a novel dredge.

'In this my invention the bucket is of the so-called clam-shell order. This bucket is supported upon a bucket-beam adapted to rise and fall with relation to the boom of the dredge, and I have devised means whereby the bucket may be forced with its open jaws against and into the material to be raised, and I have also devised means whereby the bucket may be closed positively and opened positively. The bucket-beam has combined with it a clamp to hold it in any desired position.

One part of my invention consists 111 a dredge containing the following instrumentalities, viz: a bucket-beam, a two-part opening and closing bucket mounted thereon, a slide-box on said beam, links connecting said boxand bucket, a bucket-opening chain, a

friction-fender connecting-said bucket and chain, a clamp for the bucket-beam, a drawing-down chain to force the bucketagainst the material, connections between said chain and clamp, and a closing-chain for the bucket,

substantially as will be described.

Other features of my invention will be pointed out in the'following specification and claims.

. cient portion of a dredge embodying my invention to enable the same to be understood, the chain D being partially broken out to show the chain D just like it and in line with and behind it; Fig. 2, a detail view looking at the dredge with one of the halves of the bucket removed. Fig. 2 is a sectional detail to the left of the line 00, Fig. 1. Fig. 2 shows the clamp detached. Fig. 3 is an enlarged detail showing the dredge open. Fig. 4 is an enlarged sectional detail showing part of the bucket-beam, together with the clamp for locking the same, said figure also showing the chain and devices instrumental in forcing the bucket-beam and bucket downwardly into the material to be lifted. Fig. 5 is a detailof some of the parts shown in Fig. 4, looking to the left, chiefly to show parts of the brake.

Referring to the drawings, it will be supposed that A represents some part of a scow or boat of any usual orsuitable construction,

The boom A has erected upon it, in accordance with my invention, suitable bearings for a shaft B, having loosely mounted on it, at or near the middle of its length, a sheave or chain-wheel B, to which is connected in suitable manner the drawing-down chain B the latter beingled away from the said sheave over, preferably, a roller B and thence down to and about some suitable drum actuated by power in any usual manner. Suspended from the under side of the boom, as herein shown, by eyes O are suitable chain-pulleys 0 C the chain-pulley 0' receiving a bucketopening'chain D, while the pulley 0 receives over it the bucket-closing chain D The bucket, as herein shown, is composed of two like halves E, and' is of the class of bucket known as the clam-shell,or a bucket which isopened and closed like ashell.

The particular shape of the bucket is-not of the essence of my invention, and instead of the bucket shown I may use any equivalent well-known or suitable bucket. The two halves of the bucket are, as represented, pivoted at or near each end by pivots 2 upon an ear 3, attached at 4. by suitable bolts to the lower and preferably forked end of the bucket-beam F, preferably made in two parts, as represented in the drawings. These ears have holes to receive the journals or ends of a shaft a, mounted in suitable bearings 5 at the lower end of the bucket-beam. The shaft a has upon it near the middle of its length a sheave or pulley a, having a suitable hook,

to which is connected one end of: the bucket closing chain or'contrivance D the other end of the said chain beyond the sheave 0 re ferred to, being connected to and made to cooperate in usual manner with a power-actuated drum. The shaft (1. also has fast upon it at opposite sides of the sheave or pulley a two like pulleys (L2, to which in turn are joined respectively the auxiliary chains a and at", which at their upper ends are attached respectively to eyes a a, mounted loosely upon studs a a projecting from a slide-box latitted to slide upon the bucket-beam, the said studs outside the said eye-pieces receiving the upper ends of the toggle-links b" Z2 there being like links at each side the bucket, the studs referred to constituting central pins for a toggle-joint connection.

The eye-pieces referred to, by short chains or connections a, are attached to a fenderc, having preferably an anti-friction roller 0 the said fender lying with its lower edge againsttheguideboxoutsidethebucket-beam, the roller 0 bearing against the bncket-beam, the upperend ofthe fender, as herein represented, having attached to it the bucket-openingchain D, which, after passing over the pulley G, is led in usual manner to any usual or suitable power-controlleddrum.

Referring again to the shaft B, it has fast upon it at each side the pulley B, like pulleys '13, to which are suitably jointed the lower ends of clamp-chainse, the upper ends ofsaid chains being joined to suitable eyes 6', attached to or forming parts of a clamp of suitable construction, which may be operated to grasp the bucket-beam and hold the same firmly while the chain B is being drawn upon to force the open bucket into the mate rial, the said clamps also acting tohold down thesa-idbucket in any position into which it may 'beforced by the beam and until the bucket has' been closed. The clamp herein shown is a double one, because the beam is made in two parallel pieces.- This clamp (shown separately in Fig. 2 consists, essentially, of a center-piece f, having parallel arms f f, all tied together by suitable bolts f f and f the bolt f receiving upon it clamping-blocks f, while suitably pivoted upon the bolt f are blocks f, the blocks referred to contacting with the opposite sides of the bucket-beam, and preferably the edges of thebeam againstwhich the blocks work willbe faced with metal to lessenwear. The boltj" has pivoted uponita sort of latch f, (see Fig. 4,) slotted for apart of its length andhaving its onterendlO upturned through i a hole in the center-piecefi This latch, as

wellns the center-piece, receives through it the shank of a clamp-releasing device, (shown asa hookg,) pivoted at. g upon or between armslg extended from the hub of the sheave B and attached orjointed to a strong bolt h, extendedthrongh the boom. The centerpiece f is made hollow (see Fig. 4) and receives in it a spring-pressed plunger m, bifurcated to straddle the clamp or brake releasing device g and normally keep it in position, (shownin Fig. 1,) the clamp being held at such times upon the enlarged portion of the hook g, the plunger m receding and allowing the said enlarged'portion to pass by it when the beam is forced down, the clamp then gripping the beam firmly and moving with it.

In operation let it be assumed that the bucket is elevated and closed and is about to be lowered to take dredge material. Preparatory to doing this the chain D will be slackened, and immediately the weight of the bucket on the beam will cause the beam to descend through the slide-box referred to, having the studs a a to which are connected the links 1) b and as the beam and bucket descend the bucket is opened and the lower end ofthe chain D is, duringsuch descentof the bucket, partially woundupon the sheave ct, while the two shortchains a and a are unwound from the sheaves (1 As soon as-the open bucket comes to rest upon the material, the strain will be put upon the chain 13 which will immediately cause the chains 6 to change the position of the clamps, so that they bite and engage snugly the bucketbeam, further movement of the chains in the direction of the arrow in Fig. 1 causing the opened bucket to be forced down snugly into and against the material to be lifted, and, the contact of bucket and material having been made with suflicient force, strain upon the chain B may be stopped altogether, or the movement of the chain may be madevery much slower, and then while the bucket-beam is so held down with the bucket open andin contact with the material the chain D will-be drawn upon by a drum or otherwise to rotate the shaft a, causing the small drumsa acting through the chains a a to pull upon the studs of the guide-box and, through the links 1) b effect the positix e closing of the bucket. In this condition, strain being kept upon the chain D the chainB will be slackened, letting the chain D raise the bucket and the beam until it is at the proper height, when the boom will be swung around in any usual manner to bring the bucket over the scow or other thing or place into or where the material is to be dumped, andthen the strain will be put upon the chainD to cause it to lift the slide-box, and, through the links 7) 11 open the bucket to discharge the material.

During the first part of the elevation of the bucket and beam, as described, and until the bucket clears the water, the clamp referred to rises with the beam, the chain co-operating with it' beingat such time slack and at a proper distance above the water, the brakereleasing device contacts with the brake, stops its upward movement, and tips it snfliciently to thereafter let the bucket-beam rise freely between the brake-blocks.

The length of the brake-releasing device will be greater or less, according to the depth of the water or the draft of the machine,

as it is called, so that the brake may be released sooner or later, according to the work to be done.

Prior to my invention I am not aware that a bucket-beam carrying at its lower end a two-part bucket has ever been combined with a boom in such manner as to enable the beam with its attached bucket to be forced into the material and the bucket to be closed, and this invention is not therefore to be limited to the exact means shown for accomplishing the different operations or steps indicated.

I claim l. A dredge containing the following instrumentalities, viz: a bucket-beam, a twopart opening and closing bucket mounted thereon, a slide-box on said beam, links connecting said box and bucket, a bucket-opening chain, a friction-fender connecting said bucket and chain, a clamp for the bucketbeam, a drawingdown chain to force the bucket against the material to be lifted, connections between said chain and clamps, and

a closing-chain for the bucket, substantially as described.

2. In a dredge, the followinginstrumentalities, viz: a boom, a bucket-beam having a twopart bucket pivoted thereon, means to force the bucket-beam downwardly and the bucket into the material, a clamp to hold the beam while the bucket is being closed, said clamp having a latch, and an automatic clamp-releasing device carried by the boom and in engagement with said latch, said releasing de vice normally supporting the clamp in released position, and connections between the clamp, and the means for forcing the bucketbeamsdownwardly,substantiallyas described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

ANDREW K. STONE.

Witnesses:

FREDERICK L. EMERY, FRANCES M. NOBLE. 

